Patents by Inventor Zhihong CHENG

Abstract: A low power inverter circuit includes first and second transistors that receive an input signal at their gate terminals. The first and second transistors are connected by way of their source terminals to third and fourth transistors, respectively. The third and fourth transistors are connected in parallel with fifth and sixth transistors, respectively. The third and fourth transistors are continuously switched on, and the fifth and sixth transistors are controlled in such a way to reduce short circuit current flowing through the first and second transistors when the input signal transitions from one state to another.

Abstract: A state retention power gated cell includes a logic cell arranged in two or more rows. The logic cell has an active layer including at least a first well and a second well disposed in first and second rows, respectively. In a normal operation mode, the first well is powered with a first bias voltage, the second well is powered with a second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered with VDD. In a standby mode, the first well preferably is powered down, the second well is powered with the second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered down.

Abstract: A state retention power gated (SRPG) cell includes a retention circuit coupled to a power gated circuit. The retention circuit stores state information of the power gated circuit before a low power period is started. A gated power supply coupled to the power gated circuit and to a first end of a power supply switch supplies a gated supply voltage to the power gated circuit during a non-low power period. A local power supply coupled to the retention circuit and to a second end of the power supply switch is coupled to the gated power supply in the non-low power period, and a non-gated power supply is coupled to the local power supply via an isolation element to isolate the non-gated power supply from the local power supply during the non-low power period, and to couple the non-gated power supply to the local power supply during the low power period.

Abstract: A state retention power gated cell includes a logic cell arranged in two or more rows. The logic cell has an active layer including at least a first well and a second well disposed in first and second rows, respectively. In a normal operation mode, the first well is powered with a first bias voltage, the second well is powered with a second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered with VDD. In a standby mode, the first well preferably is powered down, the second well is powered with the second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered down.

Abstract: In a master-slave flip-flop, the master latch has first and second three-state stages, and a first feedback stage. The slave latch has third and fourth three-state stages, and a second feedback stage. First and second clock switches having opposite phases are provided. The first clock switch is configured in one of the first and fourth three-state stages, and the other stage shares the first clock switch. The second clock switch is configured in one of the second and third three-state stages, and the other stage shares the second clock switch. The second three-state stage has an additional pair of complementary devices having signal paths connected in series with each other with both being gated by a data output of the slave latch. The flip-flop reduces the number of clock switches and clock switch power consumption.

Abstract: An electronic device has a power control module for causing selected functional blocks to run in a low power mode of operation, while leaving other functional blocks supplied continuously with power. A power mode control distribution network includes serially connected chains of buffers in a distribution tree for distributing power mode control signals received at a common input end to respective output ends which are connected to respective functional blocks. In the low power mode of operation the power control module causes power to be supplied continuously to output buffers at the output ends of the chains while causing power supplied to other buffers to be reduced or cut-off. The output buffers include feedback paths for causing the states of the output buffers prior to the low power mode of operation to latch during the low power mode of operation.

Abstract: A latch circuit has a tri-state gate and a reverse tri-state gate that share the same complementary controls. The reverse tri-state gate locks an output of the tri-state gate when the tri-state gate is shut-off. The complementary control signals include a first undoped polysilicon strip. The output of the reverse tri-state gate may be coupled to the output of the tri-state gate via a second undoped polysilicon strip.

Abstract: In a master-slave flip-flop, the master latch has first and second three-state stages, and a first feedback stage. The slave latch has third and fourth three-state stages, and a second feedback stage. First and second clock switches having opposite phases are provided. The first clock switch is configured in one of the first and fourth three-state stages, and the other stage shares the first clock switch. The second clock switch is configured in one of the second and third three-state stages, and the other stage shares the second clock switch. The second three-state stage has an additional pair of complementary devices having signal paths connected in series with each other with both being gated by a data output of the slave latch. The flip-flop reduces the number of clock switches and clock switch power consumption.

Abstract: An electronic device has a power control module for causing selected functional blocks to run in a low power mode of operation, while leaving other functional blocks supplied continuously with power. A power mode control distribution network includes serially connected chains of buffers in a distribution tree for distributing power mode control signals received at a common input end to respective output ends which are connected to respective functional blocks. In the low power mode of operation the power control module causes power to be supplied continuously to output buffers at the output ends of the chains while causing power supplied to other buffers to be reduced or cut-off. The output buffers include feedback paths for causing the states of the output buffers prior to the low power mode of operation to latch during the low power mode of operation.

Abstract: A system for optimizing the number of dies that can be fabricated on a wafer uses a die number optimization (DNO) routine to determine a maximum number of dies for a target die area (TDA), and generate an initial result list of die shapes that have the maximum number of dies for the TDA. Optionally, a die size optimization (DSO) routine can be executed to determine a list of die shapes having a maximum die area corresponding to the maximum number of dies, a first list of optimized die shapes having a maximum area utilization (AU) for a decreased TDA, and/or a second list of optimized die shapes having a minimum AU for an increased TDA. A candidate list (CL) of the various die shapes can be generated, and entries from the CL automatically selected and/or displayed to indicate proposed wafer layouts.

Abstract: A system for optimizing the number of dies that can be fabricated on a wafer uses a die number optimization (DNO) routine to determine a maximum number of dies for a target die area (TDA), and generate an initial result list of die shapes that have the maximum number of dies for the TDA. Optionally, a die size optimization (DSO) routine can be executed to determine a list of die shapes having a maximum die area corresponding to the maximum number of dies, a first list of optimized die shapes having a maximum area utilization (AU) for a decreased TDA, and/or a second list of optimized die shapes having a minimum AU for an increased TDA. A candidate list (CL) of the various die shapes can be generated, and entries from the CL automatically selected and/or displayed to indicate proposed wafer layouts.

Abstract: A processor with programmable virtual ports includes a plurality of in/out (IO) pins for transmitting and receiving data. The IO pins are grouped into a plurality of predefined ports, each of which has a physical address stored in one of a memory location of a memory map. The IO pins may be remapped to one or more virtual ports.

Abstract: A stepper motor controller includes control circuitry with control outputs and individual driver pulse width modulation (PWM) circuitry with individual driver PWM outputs and modulation control inputs coupled to the control outputs. There is a group of individual drivers, each one having an input coupled to one of the PWM outputs, and an output coupled to an individual driver terminal of the controller. There is common driver PWM circuitry having a common driver PWM output. A common driver having a common driver input is coupled to the common driver PWM output and a common driver output is coupled to a common driver terminal of the controller. When a coil is connected between respective driver terminals and the common driver terminal, individual PWM driver currents are supplied to the coils from the individual driver terminals and a common PWM driver current is supplied to the coils from the common driver terminal.

Abstract: In a master-slave D flip-flop, the master latch has first and second three-state stages and a feedback stage for positive feedback from the data outputs of the first and second three-state stages to the data input of the second three-state stage. The slave latch has third and fourth three-state stages and a feedback stage for positive feedback from the data outputs of the third and fourth three-state stages to the data input of the fourth three-state stage. Clock signals are applied from a clock signal source to the clock inputs of a clock switch element in one of the three-state stages whose clock signal is shared with another of the three-state stages, reducing the number of clock switches and clock switch power consumption. Data inverters also may be shared between a three-state stage of the master latch and a three-state stage of the slave latch.

Abstract: A processor with programmable virtual ports includes a plurality of in/out (IO) pins for transmitting and receiving data. The IO pins are grouped into a plurality of predefined ports, each of which has a physical address stored in one of a memory location of a memory map. The IO pins may be remapped to one or more virtual ports.

Abstract: A stepper motor controller includes control circuitry with control outputs and individual driver pulse width modulation circuitry. The individual driver pulse width modulation circuitry has individual driver pulse width modulation outputs and modulation control inputs coupled to the respective control outputs. The controller has a group of individual drivers, where each one has an individual driver input coupled to a respective one of the individual driver pulse width modulation outputs, and an individual driver output coupled to an individual driver terminal of the controller. The stepper motor controller has common driver pulse width modulation circuitry having a common driver pulse width modulation output. There is also a common driver having a common driver input coupled to the common driver pulse width modulation output and a common driver output coupled to a common driver terminal of the controller.